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Biomedical subjects

M W Fischman

Publications and source records attributed to M W Fischman.

At least 145 records · Page 8Linked to original sources
PubMed1981

Cognitive dysfunction and imipramine in outpatient depressive.

A group of moderately depressed, nonpsychotic outpatients had impaired performance on a short-term item-recognition memory task (compared with a group of matched normal controls) without evidence of impaired speed or attention on two simpler tasks. Compared with placebo, treatment with imipramine hydrochloride in a multiple crossover design using three-week treatment periods led to improved performance on the memory task without either clinically apparent improvement in depression or significantly improved performance on the other task rather than a specific impairment of short-term memory, but the data do support the presence of cognitive dysfunction in depression, even in ambulatory patients without substantial impairments of attention or motor functioning. The results also indicate that antidepressant drugs can produce improvement in cognitive function, possibly as a forerunner of clinical improvement.

Adult↗
PubMed1981

Reinforcement, skin conductance, and performance in a vigilance-reaction time task.

Three experiments were conducted using normal adults to assess the effects of contingencies of reinforcement on vigilance-reaction time performance and skin conductance. There was a significant, direct relationship between rate of skin conductance responding and speed of performance. Performance was faster and skin conductance responses were more frequent when response-contingent monetary reinforcement was available than when either feedback alone or no feedback was provided. The data suggest that central facilitating mechanisms are activated by complex interactions among several factors, including the likely consequences of task performance.

Adult↗
PubMed1981

Acute tolerance to cocaine in humans.

It has been shown that there is a dose-response relationship between blood levels of intravenously injected cocaine and magnitude of evoked heat rate (Javaid et al. 1978). This relationship also holds for inhaled cocaine while plasma levels are increasing, but the cardiovascular effects of the drug dissipate more rapidly than cocaine disappears from the plasma. This suggests that the repeated administration or sustained blood level of cocaine might produce an acute tolerance. Using an intranasal route of administration it is possible to maintain cocaine blood levels for a substantial period of time after heart rate begins to decrease from its peak levels. If an intravenous dose is then administered on top of this preexisting blood level, the effects of this second dose can be compared to the same dose administered to subjects with no preexisting blood level.

Cocaine↗
PubMed1980

Cocaine effects in sleep-deprived humans.

Eight normal healthy volunteers were tested in a reaction-time task and a work-output task after 24 and 48 h of sleep deprivation with and without 96 mg of inhaled cocaine. Cardiovascular changes and verbal report of mood change and drug effect were also monitored. Sleep deprivation produced a decrement in reaction-time performance which was reversed by inhalation of cocaine. Heart rate increased after cocaine both under non sleep-deprived conditions and sleep-deprived conditions. The magnitude of the drug-induced heart rate was, however, lower when subjects were deprived of sleep for 48 h. Verbal reports of cocaine effects were similar to those reported for amphetamine, with no evidence supporting the idea of a postdrug depression immediately after the acute effects of the drug dissipated, although some rebound effects were noted 8 h after drug administration.

Adult↗
PubMed1980

A single dose study of nabilone, a synthetic cannabinoid.

The effects of single oral doses of nabilone, a synthetic cannabinoid, were studied in four anxious volunteer subjects. Each subject had two exposures to placebo and three dose levels of nabilone at 1 week intervals in a single blind balanced Latin square design after the nabilone dose range was determined by each subject's response to a test dose. The Profile of Mood States (POMS), a self-rating adjective checklist, was used as the quantitative measure of subjective effects. The subjects performed a continuous avoidance procedure. High doses (4 or 5 mg) of nabilone produced orthostatic hypotension. Small dose-related increases in heart rate also occurred. Despite the occurrence of highly significant levels of subjective sedation, there were no significant effects of nabilone on behavior maintained by the continuous avoidance procedure. Two of these subjects experienced an anti-anxiety effect from low (1 or 2 mg) nabilone doses, but there was no statistically significant effect on the mean POMS anxiety factor for the group as a whole. In a follow-up experiment, four other anxious subjects received comparatively lower doses of nabilone. In these subjects there were no important effects on blood pressure or heart rate, and also no anti-anxiety effects.

Adult↗
PubMed1979

The effects of chlorpromazine and pentobarbital on behavior maintained by electric shock or point loss avoidance in humans.

Human volunteer subjects were trained to press a lever to avoid or escape electric shock or loss of points which could be redeemed for money at the termination of the study. The effects of pentobarbital and chlorpromazine on avoidance and escape behavior were compared. Both aversive stimuli maintained behavior which was differentially sensitive to these two drugs. Chlorpromazine caused a decrease in avoidance responding at doses which had little effect on escape responding. Pentobarbital, in contrast, suppressed avoidance responding at doses which also had a suppressant effect on escape responding.

Adult↗
PubMed1978

Cocaine plasma concentration: relation to physiological and subjective effects in humans.

Volunteer subjects with previous histories of cocaine use were administered cocaine hydrochloride intravenously or intranasally. There was a positive relationship between peak plasma concentration, physiological and subjective responses, and dose administered. The rate of cocaine disappearance after intravenous administration paralleled the drop in physiological and subjective drug effects. After intranasal administration, blood levels remained elevated for a considerably longer period.

Administration, Intranasal↗
PubMed1977

Long-term behavioral changes in the rhesus monkey after multiple daily injections of d-methylamphetamine.

The effects of multiple daily injections of d-methylamphetamine on spaced lever-press responding were investigated in the rhesus monkey. Responding was measured after single injections of d-mehtylamphetamine (0.0625-1.0 mg/kg) both before and after the monkeys were maintained on a multiple daily d-methylamphetamine injection regimen in doses ranging from 0.5 to 16 mg/kg/day. Tolerance developed to the suppressant effects of this drug on responding. As evidenced by a shift in the dose-response curve measuring number of responses and number of reinforcements per session, this tolerance persisted for at least three months after cessation of the multiple drug injection regimen. In order for tolerance to develop, it was necessary for the animals to perform the task while maintained on drug. When saline was substituted for d-methylamphetamine, no evidence of a withdrawal syndrome was seen.

Animals↗
PubMed1976

Cardiovascular and subjective effects of intravenous cocaine administration in humans.

Nine volunteer subjects were tested with intravenously administered cocaine hydrochloride in doses ranging from 4 to 32 mg, as well as 10 mg of dextroamphetamine sulfate. Measures of cardiovascular and subjective effects were made. Generally parallel dose-effect functions were obtained for heart rate, blood pressure, Addiction Research Center Inventory scores, Profile of Mood Scales, and subject ratings. A substantial effect on each of these variables was recorded after 8 mg of cocaine. The increase continued and peaked at approximately 16 mg after which it usually leveled off. Ten milligrams of dextroamphetamine generally had an effect comparable to 8 to 16 mg of cocaine.

Adult↗
PubMed1976

Effects of chlorpromazine on avoidance and escape responding in humans.

The effects of chlorpromazine on shock avoidance and escape responding were determined using four human subjects lever pressing on a modified free operant avoidance schedule. Doses of chlorpromazine ranging from 50 to 100 mg and shock levels ranging from 0.35 to 3.0 mA were used. In general, the results showed that chlorpromazine suppressed avoidance responding at doses which did not suppress escape responding.

Adult↗
PubMedDate not supplied

Single-dose study of nabilone in anxious volunteers.

The effects of single oral doses of nabilone, a synthetic cannabinoid, were studied in eight anxious volunteer subjects. Each subject had two exposures to placebo and three dose levels of nabilone at one-week intervals in a single-blind balanced Latin-square design after the nabilone dose range was determined by each subject's response to a test dose. Heart rate and blood pressure were monitored. The Profile of Mood States (POMS), a self-rating adjective checklist, was used as the quantitative measure of subjective effects. Four subjects performed a continuous avoidance procedure. High doses (4 or 5 mg) of nabilone produced orthostatic hypotension in these subjects. Mild dose-related increases in heart rate also occurred. Despite the occurrence of highly significant levels of sedation, there were no significant effects of nabilone on the continuous avoidance procedure. Two of these four subjects experienced an antianxiety effect from low (1 or 2 mg) nabilone doses. Four other subjects received comparatively lower doses of nabilone and performed on three behavioral tasks at intervals before and after drug: a recognition memory procedure, a task requiring spaced responding at a controlled rate, and a reaction time task. In these subjects there were no reliable effects on blood pressure or heart rate, no significant subjective effects on the POMS, and no antianxiety effects. Drug effects were also minimal on the three behavioral tasks.

Adult↗